112 research outputs found
Using Whole-Group Metabolic Rate and Behaviour to Assess the Energetics of Courtship in Red-Sided Garter Snakes
Reproductive effort is an important aspect of life history as reproductive success is arguably the most important component of fitness. Males tend to compete for access to females and, in the process, expend their energetic capital on mate searching, maleemale competition and courtship rather than directly on offspring. Red-sided garter snakes, Thamnophis sirtalis parietalis, are an exceptional model for studying energetic costs of courtship and mating as they fast during the spring mating season, which segregates the cost of energy acquisition from the cost of courtship and mating. However, measuring an individual male\u27s metabolic rate during courtship is complicated by the fact that male courtship behaviour in redsided garter snakes is dependent on both the detection of a female sexual attractiveness pheromone and on facilitated courtship (i.e. vigorous courtship is only exhibited in the presence of other males). Thus, traditional techniques of placing a mask over the head of individuals would prevent male courtship behaviour, and single animals placed in a flow-through chamber would not yield ecologically realistic levels of courtship, which are only seen in the context of a mating aggregation in this species. Because of these difficulties, we placed groups of males in a flow-through metabolic chamber together with a single female whose respiratory gases were vented outside the chamber to yield a whole-group metabolic rate during competitive courtship. We also measured the standard metabolic rates (SMR) of the males individually for comparison with active metabolic rates. Conservative estimates of peak group metabolic rates during courtship are 10e20 times higher than resting group metabolic rate, which was 1.88 times higher than SMR. These measurements, coupled with the fact that these males are aphagous during the breeding, indicates that costs of courtship may be high for males and has implications for the male mating tactics in this system
Traditional and Applied Graduate Education: Special Challenges
This article addresses the difference in philosophy and instruction methods in communication graduate programs of the traditional and applied graduate education. Both the traditional and the applied programs are equal in intellectual challenges but with significant differences recognized and accounted for in faculty decision-making associated with course selection, content, and instructional strategy. Graduate programs that contain elements of both models are the more common in our field and face special challenges. In conclusion, administrators must establish and focus upon mutual respect for the commonalities held by the two approaches to graduate education and the support they have for each other, rather than the differences
Overcoming Resistance to Instructional Technology
This article discusses the significance of instructional technology to communication departments and presents actions which can take to overcome faculty resistance to instructional technology. One of the major values of instructional technology is that rather than minimizing the role of the human instructor, that instructor actually uncovers a means for greater learning impact upon individuals in the class. The massive utilization of communication technology in distance learning efforts across the nation clearly demonstrates the effective utilization of instructional strategies in one context from which we can make appropriate adjustments to another context, the on-site classroom
Using Assessment and Feedback to Enhance Learning: Examining the Relationship Between Teachers’ Reported Use of Assessment and Feedback and Student Performance in AP Biology
This paper analyzes a national sample of teachers’ self-reported use of assessment and feedback in Advanced Placement (AP) biology classrooms. Descriptive statistics of what teachers reported doing in these two areas are discussed, followed by the identification of reported teaching practices variables that were found to be significantly related with student performance on AP biology exams. All the significant variables found are exemplars of authentic assessment and feedback practices and techniques. The study provides valuable information on the types of assessment and feedback practices currently being employed by teachers, and shows the relationship of such practices with actual student outcomes
The Maine Annex, vol. 2, no. 5
The Maine Annex covers the pending visit of Pulitzer Prize winner and Maine author and poet, Robert P. Tristram Coffin, a native of Brunswick, Maine
Remyelination Reporter Reveals Prolonged Refinement of Spontaneously Regenerated Myelin
Neurological diseases and trauma often cause demyelination, resulting in the disruption of axonal function and integrity. Endogenous remyelination promotes recovery, but the process is not well understood because no method exists to definitively distinguish regenerated from preexisting myelin. To date, remyelinated segments have been defined as anything abnormally short and thin, without empirical data to corroborate these morphological assumptions. To definitively identify regenerated myelin, we used a transgenic mouse with an inducible membrane-bound reporter and targeted Cre recombinase expression to a subset of glial progenitor cells after spinal cord injury, yielding remarkably clear visualization of spontaneously regenerated myelin in vivo. Early after injury, the mean length of sheaths regenerated by Schwann cells and oligodendrocytes (OLs) was significantly shorter than control, uninjured myelin, confirming past assumptions. However, OL-regenerated sheaths elongated progressively over 6 mo to approach control values. Moreover, OL-regenerated myelin thickness was not significantly different from control myelin at most time points after injury. Thus, many newly formed OL sheaths were neither thinner nor shorter than control myelin, vitiating accepted dogmas of what constitutes regenerated myelin. We conclude that remyelination, once thought to be static, is dynamic and elongates independently of axonal growth, in contrast to stretch-based mechanisms proposed in development. Further, without clear identification, past assessments have underestimated the extent and quality of regenerated myelin
The Maine Annex, vol. 2, no. 8
The Maine Annex covers Erroll E. Murphy\u27s trip to Washington, D.C. as the University of Maine Annex campus representative to the National Association of Veteran Trainees. Murphy was among the World War II Veterans seeking support for Edith Nourse Rogers of Massachusetts bill H.R. 870, to increase Veterans\u27 subsistence payments
The Ursinus Weekly, May 20, 1971
U.C. Century II fund drive commences; Goal for \u2770-\u2775 set at 5.5 million • Samuel L. Gandy speaks June 6th • Pancoast takes sabbatical leave • Ursinus gives merit scholarships • Women\u27s curfews change; Weekend hours abolished • What has become of APEs? • Editorial: Apathy kills • Focus: Selby Nera • U.S.G.A. wrap-up 1970-71: A year in pursuit of progress • Appearance & reality? • Double standard is alive and living in Collegeville • Movie critic: Little big man • Student Union and Bomberger renovation to begin soon • Faculty portrait: Dr. Ray Schultz • U.C. English comprehensive to present times-one view • U.C. President William Pettit reflects on past year, his first as President • Mrs. Watson has perfected the art of winning • After four years • Varsity golf: Linksmen finish 6-8 • D. Larson pitches 3 hitter • Final examination schedulehttps://digitalcommons.ursinus.edu/weekly/1147/thumbnail.jp
Blind Test of Methods for Obtaining 2-D Near-Surface Seismic Velocity Models from First-Arrival Traveltimes
Seismic refraction methods are used in environmental and engineering studies to image the
shallow subsurface. We present a blind test of inversion and tomographic refraction analysis
methods using a synthetic first-arrival-time dataset that was made available to the community in
2010. The data are realistic in terms of the near-surface velocity model, shot-receiver geometry
and the data’s frequency and added noise. Fourteen estimated models were determined by ten
participants using eight different inversion algorithms, with the true model unknown to the
participants until it was revealed at a session at the 2011 SAGEEP meeting. The estimated
models are generally consistent in terms of their large-scale features, demonstrating the
robustness of refraction data inversion in general, and the eight inversion algorithms in
particular. When compared to the true model, all of the estimated models contain a smooth
expression of its two main features: a large offset in the bedrock and the top of a steeply dipping
low-velocity fault zone. The estimated models do not contain a subtle low-velocity zone and
other fine-scale features, in accord with conventional wisdom. Together, the results support
confidence in the reliability and robustness of modern refraction inversion and tomographic
Methods
The Naturalized Gender Order Of Rock and Roll
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66933/2/10.1177_019685999501900104.pd
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